Variations in metabolite profiles of serum coronas produced around PEGylated liposomal drugs by surface property.

Understanding biomolecular coronas that spontaneously occur around nanocarriers (NCs) in biological fluids is critical to nanomedicine as the coronas influence the behaviors of NCs in biological systems. In contrast to extensive investigations of protein coronas over the past decades, understanding of the coronas of biomolecules beyond proteins, e.g., metabolites, has been rather limited despite such biochemicals being ubiquitously involved in the coronas, which may influence the bio-nano interactions and thus exert certain biological impacts. In this study, serum biomolecular coronas, in particular the coronas of metabolites including lipids, around PEGylated doxorubicin-loaded liposomes with different surface property were investigated. The surface properties of liposomal drugs varied in terms of surface charge and PEGylation density by employing different ionic lipids such as DOTAP and DOPS and different concentrations of PEGylation lipids in liposome formulation. Using the liposomal drugs, the influence of the surface property on the serum metabolite profiles in the coronas was traced for target molecules of 220 lipids and 88 hydrophilic metabolites. From the results, it was found that metabolites rather than proteins mainly constitute the serum coronas on the liposomal drugs. Most of the serum metabolites were found to be retained in the coronas but with altered abundances. Depending on their class, lipids exhibited a different dependence on the surface property. However, overall, lipids appeared to favor corona formation on more negatively charged and PEGylated surfaces. Hydrophilic metabolites also exhibited a similar propensity for corona formation. This study on the surface dependence of metabolite corona formation provides a fundamental contribution toward attaining a comprehensive understanding of biomolecular coronas, which will be critical to the development of efficient nanomedicine.